No. XXII.] APPENDIX. 309 



inspectors are subjected to some torture when I state that rigid silence is 

 expected in the room they sit in, and the whole number of females daily 

 perform their allotted duties without gossip of any description. 



The strength of the paper made in the manner above described is very 

 great when we consider the nature of the water-mark, which is calculated 

 to render it weaker than it would otherwise be. To be sure that no change 

 is being made in the materials, its strength is actually tested by a simple 

 machine ; and a sheet of note-paper, although so thin, will always bear a 

 weight of fifty pounds, and sometimes as much as seventy-five pounds, 

 before it breaks. 



The printing-ink for the bank-note is also a matter which has re- 

 ceived attention. The properties of ink, when carefully prepared, are 

 very curious and require considerable judgment to adjust them to par- 

 ticular papers. To Mr. Winstone, the printing ink manufacturer, has 

 been entrusted the preparation and adaptation of the ink for the note, 

 as it required somewhat careful treatment for the peculiar arrangement 

 of the blacks and lights in the note. The black colouring material is made 

 by burning coal-tar naphtha, and collecting the smoke in large rooms. 

 This smoke or lamp-black is placed in a retort, and heated to a high 

 temperature, to drive off all volatile matters, when the ink becomes con- 

 solidated and improved in colour. This is subsequently ground with a 

 suitable varnish to a proper consistence to rest firmly on the delicate 

 lines of the Britannia, without spreading to produce a rugged edge, and 

 yet completely fill the black patches of the letters of the designation. 

 In the bank-note it is also expected that the ink should dry sufficiently 

 to allow handling immediately after being printed, a property which Mr. 

 Winstone's chemical knowledge has enabled him to produce. To my mind, 

 whatever may have been the results heretofore attained, the typographical 

 art for rapid production has much to be improved by the adjustment of 

 the distributive machines to the ink, and the ink to the distributive 

 machinery. For the peculiar viscidity and tenacity of the ink, the weight 

 of roller and rate of motion should be adapted to the character of the ink. 

 At present no laws have been deduced upon this matter, but extended 

 experiments upon perfect work will, perhaps, eventually give us a know- 

 ledge of the relation which ought to exist between roller and ink. 



In my original proposition to the Governor of the Bank, I suggested 

 that, in the first instance, the hand-press should be employed, because by 

 it the pressman could more perfectly manage the ink, and have everything 

 requisite for the adaptation of the typographical system to the bank-notes 

 before the selection of a printing machine was made. The authorities of 

 the Bank, however, determined, at the instance of Mr. Hensman and Mr. 

 Coe, at once to attempt the use of the machine, and these gentlemen made 

 an investigation of nearly every printing machine in use before the kind of 

 machine to be employed was selected. It was found that the machines in 

 greatest repute by the best printers were not sufficiently perfect for the 

 Bank, inasmuch as the type did not always fall in the same place in regard 

 to the tympan, a circumstance which interfered with the overlaying, so 

 necessary to fine work, and in no case was the inking apparatus sufficiently 

 good for this class of work. 



For the cheques they considered that the double platten was the best 

 machine which was in active operation at that time. For that reason a 



